All of the patents cited throughout this specification are hereby entirely incorporated herein.
Historically, solvent dyes have been utilized as colorants within waxes, particularly candles. Although these dyes provide good coloring throughout the wax medium, solvent dyes are difficult to handle (powder or dust form), easily stain a myriad of substrates (including a colorist's skin), migrate out of hardened wax to discolor its storage wrapper or its handler's skin, clog burning candle wicks with solid particulate dye, and the like. It is therefore highly desirable to find effective alternatives to such poorly performing wax dyes. There exists a need then to produce a dye which provides effective, thorough, and homogeneous colorations to wax, is easy to handle, will not migrate out of hardened wax, and will not clog a candle wick with solid particles.
It has been found that the utilization of ester capped polyoxyalkylene colorants provide all of the requisite beneficial properties outlined above which are desirable within wax compositions, particularly within candles. Such colorants are present in a neat liquid state at 25.degree. C. which thus facilitates handling and substantially eliminates any wick clogging problems. Furthermore, such colorants are extremely stable when dispersed within a hardened wax medium and therefore cannot migrate out of solution. Also, an additive, such as stearic acid, may be introduced within such wax compositions in order to produce a crayon composition which exhibits the same types of beneficial properties as outlined above for candles, except for the non-clogging characteristics of a wick.
Ester capped polyoxyalkylene colorants are known as fugitive tints for certain textiles, in particular to color code threads during production and/or finishing operations. For example, U.S. Pat. No. 4,167,510, to Brendle discloses the same ester capped colorants as used in the present candle compositions but for use in textile and thread tinting applications. Patentee does not discuss nor allude to any other coloring methods other than textiles for his ester capped colorants. Other possible esterified colorants have been taught within U.S. Pat. No. 4,871,371, to Harris; however, these colorants are utilized solely for the purpose of coloring aqueous or non-aqueous liquids, not waxes, and do not require a fatty acid moiety. Patentee does disclose the addition of alkoxylated fatty acids as diluents for his colorants, but makes no mention of a fatty acid group on the colorant itself. Esterified polymeric colorants within liquid petroleum or mineral oil compositions are taught within U.S. Pat. No. 3,734,857, to Moiso et al., and U.S. Pat. No. 5,145,573, to Riedel et al.; however, the possible esters within these references are limited to short chain (C.sub.1 -C.sub.4) moieties. Therefore these patents neither teach nor fairly suggest the specific candle compositions of the present invention.